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1.
bioRxiv ; 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38496520

RESUMO

New agents are needed that selectively kill cancer cells without harming normal tissues. The TRAIL ligand and its receptors, DR5 and DR4, exhibit cancer-selective toxicity, but TRAIL analogs or agonistic antibodies targeting these receptors have not received FDA approval for cancer therapy. Small molecules for activating DR5 or DR4 independently of protein ligands may bypass some of the pharmacological limitations of these protein drugs. Previously described Disulfide bond Disrupting Agents (DDAs) activate DR5 by altering its disulfide bonding through inhibition of the Protein Disulfide Isomerases (PDIs) ERp44, AGR2, and PDIA1. Work presented here extends these findings by showing that disruption of single DR5 disulfide bonds causes high-level DR5 expression, disulfide-mediated clustering, and activation of Caspase 8-Caspase 3 mediated pro-apoptotic signaling. Recognition of the extracellular domain of DR5 by various antibodies is strongly influenced by the pattern of DR5 disulfide bonding, which has important implications for the use of agonistic DR5 antibodies for cancer therapy. Disulfide-defective DR5 mutants do not activate the ER stress response or stimulate autophagy, indicating that these DDA-mediated responses are separable from DR5 activation and pro-apoptotic signaling. Importantly, other ER stressors, including Thapsigargin and Tunicamycin also alter DR5 disulfide bonding in various cancer cell lines and in some instances, DR5 mis-disulfide bonding is potentiated by overriding the Integrated Stress Response (ISR) with inhibitors of the PERK kinase or the ISR inhibitor ISRIB. These observations indicate that the pattern of DR5 disulfide bonding functions as a sensor of ER stress and serves as an effector of proteotoxic stress by driving extrinsic apoptosis independently of extracellular ligands.

2.
BMC Mol Cell Biol ; 25(1): 2, 2024 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-38172660

RESUMO

BACKGROUND: Fas-associated factor 1 (FAF1) is a multidomain protein that interacts with diverse partners to affect numerous cellular processes. Previously, we discovered two Small Ubiquitin-like Modifier (SUMO)-interacting motifs (SIMs) within FAF1 that are crucial for transcriptional modulation of mineralocorticoid receptor. Recently, we identified Sin3A-associated protein 130 (SAP130), a putative sumoylated protein, as a candidate FAF1 interaction partner by yeast two-hybrid screening. However, it remained unclear whether SAP130 sumoylation might occur and functionally interact with FAF1. RESULTS: In this study, we first show that SAP130 can be modified by SUMO1 at Lys residues 794, 878 and 932 both in vitro and in vivo. Mutation of these three SUMO-accepting Lys residues to Ala had no impact on SAP130 association with Sin3A or its nuclear localization, but the mutations abrogated the association of SAP130 with the FAF1. The mutations also potentiated SAP130 trans-repression activity and attenuated SAP130-mediated promotion of cell growth. Additionally, SUMO1-modified SAP130 was less stable than unmodified SAP130. Transient transfection experiments further revealed that FAF1 mitigated the trans-repression and cell proliferation-promoting functions of SAP130, and promoted SAP130 degradation by enhancing its polyubiquitination in a sumoylation-dependent manner. CONCLUSIONS: Together, these results demonstrate that sumoylation of SAP130 regulates its biological functions and that FAF1 plays a crucial role in controlling the SUMO-dependent regulation of transcriptional activity and protein stability of SAP130.


Assuntos
Sumoilação , Fatores de Transcrição , Fatores de Transcrição/metabolismo , Ubiquitinação , Estabilidade Proteica
3.
Cell Commun Signal ; 21(1): 172, 2023 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-37430297

RESUMO

BACKGROUND: Protein phosphatase 2A (PP2A) is one of the major protein phosphatases in eukaryotic cells and is essential for cellular homeostasis. PP2A is a heterotrimer comprising the dimeric AC core enzyme and a highly variable regulatory B subunit. Distinct B subunits help the core enzyme gain full activity toward specific substrates and contribute to diverse cellular roles of PP2A. PP2A has been thought to play a tumor suppressor and the B56γ3 regulatory subunit was shown to play a key tumor suppressor regulatory subunit of PP2A. Nevertheless, we uncovered a molecular mechanism of how B56γ3 may act as an oncogene in colorectal cancer (CRC). METHODS: Polyclonal pools of CRC cells with stable B56γ3 overexpression or knockdown were generated by retroviral or lentiviral infection and subsequent drug selection. Co-immunoprecipitation(co-IP) and in vitro pull-down analysis were applied to analyze the protein-protein interaction. Transwell migration and invasion assays were applied to investigate the role of B56γ3 in affecting motility and invasive capability of CRC cells. The sensitivity of CRC cells to 5-fluorouracil (5-FU) was analyzed using the PrestoBlue reagent assay for cell viability. Immunohistochemistry (IHC) was applied to investigate the expression levels of phospho-AKT and B56γ3 in paired tumor and normal tissue specimens of CRC. DataSets of TCGA and GEO were analyzed to investigate the correlation of B56γ3 expression with overall survival rates of CRC patients. RESULTS: We showed that B56γ3 promoted epithelial-mesenchymal transition (EMT) and reduced the sensitivity of CRC cells to 5-FU through upregulating AKT activity. Mechanistically, B56γ3 upregulates AKT activity by targeting PP2A to attenuate the p70S6K-mediated negative feedback loop regulation on PI3K/AKT activation. B56γ3 was highly expressed and positively correlated with the level of phospho-AKT in tumor tissues of CRC. Moreover, high B56γ3 expression is associated with poor prognosis of a subset of patients with CRC. CONCLUSIONS: Our finding reveals that the B56γ3 regulatory subunit-containing PP2A plays an oncogenic role in CRC cells by sustaining AKT activation through suppressing p70S6K activity and suggests that the interaction between B56γ3 and p70S6K may serve as a therapeutic target for CRC. Video Abstract.


Assuntos
Neoplasias Colorretais , Transição Epitelial-Mesenquimal , Humanos , Proteína Fosfatase 2 , Proteínas Proto-Oncogênicas c-akt , Retroalimentação , Proteínas Quinases S6 Ribossômicas 70-kDa , Fosfatidilinositol 3-Quinases , Fluoruracila
4.
J Chin Med Assoc ; 86(5): 494-498, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-36740745

RESUMO

BACKGROUND: In patients with advanced osteoarthritis (OA) of the bilateral knees, uncertainty remains as to whether simultaneous bilateral total knee arthroplasty (SiTKA) or staged TKA (StTKA) is the treatment of choice. The purpose of this study was to investigate the safety and relative cost of SiTKA vs StTKA in Taiwan patients. METHODS: Using the Big Data Center of Taipei Veterans General Hospital, we retrospectively reviewed all patients who underwent SiTKA or StTKA due to OA or spontaneous osteonecrosis of the knee from January 2011 to December 2016. We assessed length of stay, transfusion rate, early postoperative complications, 30- and 90-day readmission rate, 1-year reoperation rate, and the indication for reoperation. Furthermore, we analyzed the total cost of the two groups, including reimbursement from the national health insurance (NHI), cost of the procedures, and net income from each case. RESULTS: A total of 2016 patients (1565 SiTKA and 451 StTKA) were included in this study. The two groups had no significant differences in rates of complications, 30- and 90-day readmission, or 1-year reoperation. The length of stay was on average 5.0 days longer for StTKA ( p < 0.01). In terms of cost, all categories of medical costs were significantly lower for SiTKA, while the net hospital income was significantly higher for StTKA. CONCLUSION: SiTKA is a safe and cost-effective surgery. Both SiTKA and StTKA have similar rates of postoperative complications, readmission and reoperation, but SiTKA significantly reduces medical expenses for both the patient and the NHI.


Assuntos
Artroplastia do Joelho , Osteoartrite do Joelho , Humanos , Artroplastia do Joelho/efeitos adversos , Estudos Retrospectivos , Taiwan , Tempo de Internação , Complicações Pós-Operatórias/etiologia , Resultado do Tratamento
5.
Neurol Sci ; 44(6): 2003-2015, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36689009

RESUMO

BACKGROUND: Essential tremor (ET) is an autosomal dominant inheritance disorder. Mutations in fusion sarcoma (FUS), mitochondrial serine peptidase 2 (HTRA2), teneurin transmembrane protein 4 (TENM4), sortilin1 (SORT1), SCN11A, and notch2N-terminal-like (NOTCH2NLC) genes are associated with familial ET. METHODS: A proband with ET was tested using whole-exome sequencing and repeat-primed polymerase chain reaction. Subsequently, the family members were screened for the suspected mutation, and the results were verified using Sanger sequencing. The relationship between pedigree and phenotype was also analyzed, and structural and functional changes in the variants were predicted using bioinformatics analysis. RESULTS: In a family with ET, the proband (III4) and the proband's father (II1), grandfather (I1), uncle (II2), and cousin (III5) all presented with involuntary tremors of both upper limbs. The responsible mutation was identified as TENM4 c.1262C > T (p.P421L), which showed genetic co-segregation in the family survey. AlphaFold predicted a change in the spatial position of TENM4 after the P421L mutation, which may have affected its stability. AlphaFold also predicted P421L to be a deleterious variation, which would lead to lower degrees of freedom of the TENM4 protein, thereby affecting the protein's structure and stability. According to the bioinformatics analysis, TENM4 (p.P421L) may reduce the signal reaching the nucleus by affecting the expression of TENM4 messenger RNA (mRNA), thereby impairing the normal oligodendrocyte differentiation process and leading to impaired myelination. CONCLUSION: This study revealed that the TENM4 (p.P421L) pathogenic missense variation was responsible for ET in the proband.


Assuntos
Tremor Essencial , Humanos , China , Tremor Essencial/genética , Sequenciamento do Exoma , Mutação/genética , Linhagem
6.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-1000249

RESUMO

Background@#To compare risk of diabetic retinopathy (DR) between patients taking sodium-glucose cotransporter-2 inhibitors (SGLT2is) and those taking glucagon-like peptide-1 receptor agonists (GLP1-RAs) in routine care. @*Methods@#This retrospective cohort study emulating a target trial included patient data from the multi-institutional Chang Gung Research Database in Taiwan. Totally, 33,021 patients with type 2 diabetes mellitus using SGLT2is and GLP1-RAs between 2016 and 2019 were identified. 3,249 patients were excluded due to missing demographics, age <40 years, prior use of any study drug, a diagnosis of retinal disorders, a history of receiving vitreoretinal procedure, no baseline glycosylated hemoglobin, or no follow-up data. Baseline characteristics were balanced using inverse probability of treatment weighting with propensity scores. DR diagnoses and vitreoretinal interventions served as the primary outcomes. Occurrence of proliferative DR and DR receiving vitreoretinal interventions were regarded as vision-threatening DR. @*Results@#There were 21,491 SGLT2i and 1,887 GLP1-RA users included for the analysis. Patients receiving SGLT2is and GLP-1 RAs exhibited comparable rate of any DR (subdistribution hazard ratio [SHR], 0.90; 95% confidence interval [CI], 0.79 to 1.03), whereas the rate of proliferative DR (SHR, 0.53; 95% CI, 0.42 to 0.68) was significantly lower in the SGLT2i group. Also, SGLT2i users showed significantly reduced risk of composite surgical outcome (SHR, 0.58; 95% CI, 0.48 to 0.70). @*Conclusion@#Compared to those taking GLP1-RAs, patients receiving SGLT2is had a lower risk of proliferative DR and vitreoretinal interventions, although the rate of any DR was comparable between the SGLT2i and GLP1-RA groups. Thus, SGLT2is may be associated with a lower risk of vision-threatening DR but not DR development.

7.
Int J Mol Sci ; 23(19)2022 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-36233266

RESUMO

The effects of lacosamide (LCS, Vimpat®), an anti-convulsant and analgesic, on voltage-gated Na+ current (INa) were investigated. LCS suppressed both the peak (transient, INa(T)) and sustained (late, INa(L)) components of INa with the IC50 values of 78 and 34 µM found in GH3 cells and of 112 and 26 µM in Neuro-2a cells, respectively. In GH3 cells, the voltage-dependent hysteresis of persistent INa (INa(P)) during the triangular ramp pulse was strikingly attenuated, and the decaying time constant (τ) of INa(T) or INa(L) during a train of depolarizing pulses was further shortened by LCS. The recovery time course from the INa block elicited by the preceding conditioning train can be fitted by two exponential processes, while the single exponential increase in current recovery without a conditioning train was adequately fitted. The fast and slow τ's of recovery from the INa block by the same conditioning protocol arose in the presence of LCS. In Neuro-2a cells, the strength of the instantaneous window INa (INa(W)) during the rapid ramp pulse was reduced by LCS. This reduction could be reversed by tefluthrin. Moreover, LCS accelerated the inactivation time course of INa activated by pulse train stimulation, and veratridine reversed its decrease in the decaying τ value in current inactivation. The docking results predicted the capability of LCS binding to some amino-acid residues in sodium channels owing to the occurrence of hydrophobic contact. Overall, our findings unveiled that LCS can interact with the sodium channels to alter the magnitude, gating, voltage-dependent hysteresis behavior, and use dependence of INa in excitable cells.


Assuntos
Canais de Sódio , Sódio , Íons/metabolismo , Lacosamida/farmacologia , Sódio/metabolismo , Veratridina
8.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-22280238

RESUMO

Using high-throughput sequencing of the SARS-CoV-2 genome, we have analyzed 2405 PCR-positive swab samples from 2339 individuals and identified the Omicron BA.2.3.7 variant as a major lineage of the recent community outbreak in Taiwan. Since April 2022, a series of new waves of Omicron cases have surfaced in Taiwan and spread throughout the island. We conducted genomic surveillance with a high success rate and have submitted 1966 full-length Omicron sequences to GISAID. This has permitted identification of signature amino acid changes (ORF1a:L631F, S:K97E, N:M322I) in 1584 (80.6%) of the translated SARS-CoV-2 sequences. The newly established BA.2.3.7 lineage, which is relatively common in Asian countries, is now persistently present in Taiwan. By June 2022 this dominant strain had established a substantial existence in the sequence pool, resulting in additional mutations. The rapid spread and expansion of the Omicron BA.2.3.7 lineage in Asia has had an important socioeconomic impact on health policy.

9.
Int J Mol Sci ; 23(16)2022 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-36012718

RESUMO

The non-linear voltage-dependent hysteresis (Hys(V)) of voltage-gated ionic currents can be robustly activated by the isosceles-triangular ramp voltage (Vramp) through digital-to-analog conversion. Perturbations on this Hys(V) behavior play a role in regulating membrane excitability in different excitable cells. A variety of small molecules may influence the strength of Hys(V) in different types of ionic currents elicited by long-lasting triangular Vramp. Pirfenidone, an anti-fibrotic drug, decreased the magnitude of Ih's Hys(V) activated by triangular Vramp, while dexmedetomidine, an agonist of α2-adrenoceptors, effectively suppressed Ih as well as diminished the Hys(V) strength of Ih. Oxaliplatin, a platinum-based anti-neoplastic drug, was noted to enhance the Ih's Hys(V) strength, which is thought to be linked to the occurrence of neuropathic pain, while honokiol, a hydroxylated biphenyl compound, decreased Ih's Hys(V). Cell exposure to lutein, a xanthophyll carotenoid, resulted in a reduction of Ih's Hys(V) magnitude. Moreover, with cell exposure to UCL-2077, SM-102, isoplumbagin, or plumbagin, the Hys(V) strength of erg-mediated K+ current activated by triangular Vramp was effectively diminished, whereas the presence of either remdesivir or QO-58 respectively decreased or increased Hys(V) magnitude of M-type K+ current. Zingerone, a methoxyphenol, was found to attenuate Hys(V) (with low- and high-threshold loops) of L-type Ca2+ current induced by long-lasting triangular Vramp. The Hys(V) properties of persistent Na+ current (INa(P)) evoked by triangular Vramp were characterized by a figure-of-eight (i.e., ∞) configuration with two distinct loops (i.e., low- and high-threshold loops). The presence of either tefluthrin, a pyrethroid insecticide, or t-butyl hydroperoxide, an oxidant, enhanced the Hys(V) strength of INa(P). However, further addition of dapagliflozin can reverse their augmenting effects in the Hys(V) magnitude of the current. Furthermore, the addition of esaxerenone, mirogabalin, or dapagliflozin was effective in inhibiting the strength of INa(P). Taken together, the observed perturbations by these small-molecule modulators on Hys(V) strength in different types of ionic currents evoked during triangular Vramp are expected to influence the functional activities (e.g., electrical behaviors) of different excitable cells in vitro or in vivo.


Assuntos
Amino Álcoois , Caprilatos , Transporte de Íons , Sódio
10.
Int J Mol Sci ; 23(14)2022 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-35887240

RESUMO

Carbamazepine (CBZ, Tegretol®) is an anticonvulsant used in the treatment of epilepsy and neuropathic pain; however, several unwanted effects of this drug have been noticed. Therefore, the regulatory actions of CBZ on ionic currents in electrically excitable cells need to be reappraised, although its efficacy in suppressing voltage-gated Na+ current (INa) has been disclosed. This study was undertaken to explore the modifications produced by CBZ on ionic currents (e.g., INa and erg-mediated K+ current [IK(erg)]) measured from Neuro-2a (N2a) cells. In these cells, we found that this drug differentially suppressed the peak (transient, INa(T)) and sustained (late, INa(L)) components of INa in a concentration-dependent manner with effective IC50 of 56 and 18 µM, respectively. The overall current-voltage relationship of INa(T) with or without the addition of CBZ remained unchanged; however, the strength (i.e., ∆area) in the window component of INa (INa(W)) evoked by the short ascending ramp pulse (Vramp) was overly lessened in the CBZ presence. Tefluthrin (Tef), a synthetic pyrethroid, known to stimulate INa, augmented the strength of the voltage-dependent hysteresis (Hys(V)) of persistent INa (INa(P)) in response to the isosceles-triangular Vramp; moreover, further application of CBZ attenuated Tef-mediated accentuation of INa(P)'s Hys(V). With a two-step voltage protocol, the recovery of INa(T) inactivation seen in Neuro-2a cells became progressively slowed by adding CBZ; however, the cumulative inhibition of INa(T) evoked by pulse train stimulation was enhanced during exposure to this drug. Neuro-2a-cell exposure to CBZ (100 µM), the magnitude of erg-mediated K+ current measured throughout the entire voltage-clamp steps applied was mildly inhibited. The docking results regarding the interaction of CBZ and voltage-gate Na+ (NaV) channel predicted the ability of CBZ to bind to some amino-acid residues in NaV due to the existence of a hydrogen bond or hydrophobic contact. It is conceivable from the current investigations that the INa (INa(T), INa(L), INa(W), and INa(P)) residing in Neuro-2a cells are susceptible to being suppressed by CBZ, and that its block on INa(L) is larger than that on INa(T). Collectively, the magnitude and gating of NaV channels produced by the CBZ presence might have an impact on its anticonvulsant and analgesic effects occurring in vivo.


Assuntos
Anticonvulsivantes , Crista Neural , Animais , Anticonvulsivantes/farmacologia , Benzodiazepinas , Carbamazepina/farmacologia , Linhagem Celular , Camundongos , Sódio
11.
Front Cardiovasc Med ; 9: 925711, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35722106

RESUMO

Background: Spontaneous splenic rupture (SSR) is a rare, often life-threatening, acute abdominal injury that requires immediate diagnosis and early treatment. SSR is mainly treated surgically or conservatively. A few cases of interventional embolization for SSRs have been reported. Case Presentation: A 30-year-old male patient complaining mainly of left upper abdominal pain underwent emergency abdominal computed tomography (CT) and showed enlargement of the spleen with a massive mixed-density shadow approximately 10.0 × 8.0 × 12.5 cm in size. The boundary was unclear and showed obvious progressive enhancement. Considering the intrasplenic tumor lesions with rupture and hemorrhage, the possibility of vascular tumors was high, with intraperitoneal blood and fluid accumulation. Digital subtraction angiography of the splenic arteriography and embolization of the ruptured splenic artery branches were performed. Postoperative hemoglobin progressively decreased, inflammatory indicators, such as white blood cell counts, procalcitonin (PCT), and C-reactive protein (CRP) were significantly increased, and 2 days after embolization, the patient developed severe hypoxemia, shock, pulmonary edema, and acute respiratory distress syndrome. CT re-examination 9 days after embolization showed reduced lesion absorption. After stabilization of the condition, splenectomy was performed, and postoperative platelet count increase, anticoagulant improvement, and discharge were observed. Postoperative pathological examination revealed extensive hemorrhage and necrosis, vascular tissue with abnormal hyperplasia in the surrounding area, vascular tissue in the bleeding area and outer wall (elastic fiber staining +), and local myofibroblast hyperplasia. Immunohistochemistry showed actin (SM +) and Ki67 (10% +). Conclusion: SSR caused by splenic hemangioma is rare, and the choice between surgical treatment or splenic artery embolization remains dependent on the patient's hemodynamic stability and imaging findings.

12.
Front Surg ; 9: 875484, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35521428

RESUMO

Background: The analgesic effect produced by the intra-arterial injection of lidocaine in patients undergoing uterine artery embolization has been proven to be safe and effective. Nevertheless, a significant degree of pain is typically experienced after the operation, and pain management is crucial. Methylprednisolone, which provides an anti-inflammatory effect, is widely used in the treatment of several diseases. To date, methylprednisolone has not been used after uterine artery embolization. Methods: A total of 131 patients with uterine leiomyoma were retrospectively enrolled. Forty-five patients (control group) were treated with embolized microspheres for bilateral uterine artery embolization. Fifty (study group) and 36 (lidocaine group) patients were administered lidocaine mixed with embolized microspheres during embolization, and in addition, the study group was administered methylprednisolone. Completed pain scales at different time points during surgery were obtained from patients undergoing uterine artery embolization. Efficacy against pain was evaluated by comparing the pain score, inflammatory index, and use of sufentanil within 24 h followed by a Kruskal-Wallis Test and a least significant difference post-hoc analysis. Results: The postoperative pain scores at 1, 4, and 7 h after uterine artery embolization in the study group (3.08 ± 2.09, 2.46 ± 1.93, and 2.38 ± 1.85, respectively) were significantly lower than those in the control group (4.84 ± 2.36, 4.16 ± 1.87, and 3.56 ± 1.93, respectively) and the lidocaine group (3.50 ± 2.10, 3.30 ± 1.88, and 3.28 ± 1.89, respectively). At the first 24 h after embolization, the total usage of sufentanil in the study group (31.4 ± 4.16) was significantly lower than those in the control group (45.7 ± 6.51) and the lidocaine group (38.3 ± 6.25). At 1 and 4 h, the pain scores of the lidocaine group were significantly lower than those of the control group. In addition, at the first 24 h after embolization, the total usage of sufentanil in the lidocaine group was significantly lower than that in the control group. Conclusion: Lidocaine in combination with methylprednisolone can significantly alleviate pain and reduce the usage of sufentanil after bilateral uterine artery embolization. Thus, methylprednisolone is a recommended addition to the therapeutic regimen after embolization.

13.
Cancer Lett ; 534: 215604, 2022 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-35247515

RESUMO

Breast cancer mortality remains unacceptably high, indicating a need for safer and more effective therapeutic agents. Disulfide bond Disrupting Agents (DDAs) were previously identified as a novel class of anticancer compounds that selectively kill cancers that overexpress the Epidermal Growth Factor Receptor (EGFR) or its family member HER2. DDAs kill EGFR+ and HER2+ cancer cells via the parallel downregulation of EGFR, HER2, and HER3 and activation/oligomerization of Death Receptors 4 and 5 (DR4/5). However, the mechanisms by which DDAs mediate these effects are unknown. Affinity purification analyses employing biotinylated-DDAs reveal that the Protein Disulfide Isomerase (PDI) family members AGR2, PDIA1, and ERp44 are DDA target proteins. Further analyses demonstrate that shRNA-mediated knockdown of AGR2 and ERp44, or expression of ERp44 mutants, enhance basal DR5 oligomerization. DDA treatment of breast cancer cells disrupts PDIA1 and ERp44 mixed disulfide bonds with their client proteins. Together, the results herein reveal DDAs as the first small molecule, active site inhibitors of AGR2 and ERp44, and demonstrate roles for AGR2 and ERp44 in regulating the activity, stability, and localization of DR4 and DR5, and activation of Caspase 8.


Assuntos
Neoplasias da Mama , Dissulfetos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Morte Celular , Dissulfetos/metabolismo , Dissulfetos/uso terapêutico , Receptores ErbB/metabolismo , Feminino , Humanos , Proteínas de Membrana , Chaperonas Moleculares/metabolismo , Mucoproteínas , Proteínas Oncogênicas/genética , Isomerases de Dissulfetos de Proteínas/genética , Isomerases de Dissulfetos de Proteínas/metabolismo , Proteínas , Receptores de Morte Celular
14.
Sci Rep ; 12(1): 241, 2022 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-34997132

RESUMO

The prognosis of patients with human epidermal growth factor receptor 2 (HER2)-positive breast cancer has considerably improved. However, no reliable treatment besides anti-HER2 strategies has been available. FTY720, a small-molecule compound used for treating refractory multiple sclerosis, has been reported to have beneficial effects against cancers. We therefore evaluated the efficacy of FTY720 in trastuzumab-resistant breast cancer cells and investigated the possible mechanism involved. This study evaluated morphological changes after FTY720 treatment. Antiproliferative WST-1 assays and LDH Cytotoxicity Assay Kits were used to determine the treatment effects of drugs, whereas Western blot analysis was used to evaluate protein expression. Apoptotic events were investigated through annexin V staining and TUNEL assays using flow cytometry. FTY720 was effective in trastuzumab-resistant breast cancer cell lines despite the presence of PIK3CA mutation. Studied on a xenograft mouse model, FTY720-treated groups had statistically significantly poorer HCC1954 xenograft growth in vivo compared with the control group. Our findings suggest that FTY720 can overcome resistance to trastuzumab therapy in patients with HER2-positive breast cancer, with FTY720 plus trastuzumab might offer even better efficacy in vitro and in vivo.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Cloridrato de Fingolimode/administração & dosagem , Receptor ErbB-2/genética , Animais , Apoptose/efeitos dos fármacos , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/fisiopatologia , Linhagem Celular Tumoral , Classe I de Fosfatidilinositol 3-Quinases/genética , Classe I de Fosfatidilinositol 3-Quinases/metabolismo , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Receptor ErbB-2/metabolismo , Trastuzumab/administração & dosagem , Ensaios Antitumorais Modelo de Xenoenxerto
15.
Neurol Genet ; 8(1): e646, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34877407

RESUMO

BACKGROUND AND OBJECTIVES: To investigate the pathogenicity of 2 novel KDM5C variations, report the clinical and neuroimaging findings, and review the available literature. METHODS: Physical examinations, structural neuroimaging studies, and exome sequence analysis were performed. KDM5C constructs were used to study the effect of the variations in transfected cells. RESULTS: We identified 2 novel variations c.2233C>G and c.3392_3393delAG in the KDM5C gene harboring from 2 Chinese families with X-linked intellectual disability (ID). The affected male patients exhibited severe ID, short stature, and facial dysmorphism. The 1 with c.3392_3393delAG additionally had epilepsy and autistic spectrum disorder (ASD). Transiently transfected mutant KDM5C constructs both reduced protein expression and stability and decreased histone demethylase activities in cells. Reviewing the available literature, we found that the associated ASD tended to occur in patients with variations near the C-terminus of KDM5C. DISCUSSION: We report the clinical, molecular genetic, and pathologic features in patients with novel variations of KDM5C. The variability of the clinical phenotype in addition to an ID may associate with altered particular parts of KDM5C.

16.
Sci Rep ; 11(1): 23311, 2021 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-34857827

RESUMO

Temperature is used to trace ocean density variations, and reveals internal waves and turbulent motions in the deep ocean, called 'internal motions.' Ambient temperature detected by geophysical differential pressure gauges (DPGs) may provide year-long, complementary observations. Here, we use data from four DPGs fixed on the ocean bottom and a high-resolution temperature sensor (T-sensor) 13 m above the seafloor as a square-kilometer array deployed offshore ~ 50 km east of Taiwan facing the open Pacific Ocean to examine the impact of temperature on DPG signals related to internal motions. The DPG signals correlate with T-sensor temperature variations between 0.002 and 0.1 mHz, but have time shifts partially caused by slow thermal conduction from the ambient seafloor to the DPG chamber and partially by internal motion propagation time across the array. Applying beamforming-frequency-wavenumber analysis and linear regression to the arrayed T-sensor and DPG data, we estimate the propagating slowness of the internal motions to be between 0.5 and 7.4 s m-1 from the northwest and northeast quadrants of the array. The thermal relaxation time of the DPGs is within 103-104 s. This work shows that a systematic scan of DPG data at frequencies < 0.1 mHz may help shed light on patterns of internal wave propagation in the deep ocean, especially in multi-scale arrays.

17.
Cell Death Discov ; 7(1): 150, 2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34226528

RESUMO

Hypoxic-ischemic (HI) encephalopathy is the major cause of mortality and disability in newborns. The neurovascular unit is a major target of acute and chronic brain injury, and therapies that protect simultaneously both neurons and vascular endothelial cells from neonatal HI injury are in demand. Insulin receptors and its key downstream molecule-insulin receptor substrate -1 (IRS-1) are potential neuroprotective targets and expressed both in neuron and endothelial cells. To investigate whether IRS-1 can act similarly in neurons and vascular endothelial cells in protecting neurovascular units and brain form HI injury, we found that neuron-specific IRS-1 transgenic rats showed reduced neurovascular injury and infarct volumes, whereas endothelial-specific IRS-1 transgenic rats showed increased blood-brain barrier (BBB) disruption and exaggerated neurovascular injury after neonatal HI brain injury. Endothelial-specific IRS-1 overexpression increased vascular permeability and disassembled the tight junction protein (zonula occludens-1) complex. Inhibition of mammalian target of rapamycin (mTOR) by rapamycin preserved tight junction proteins and attenuated BBB leakage and neuronal apoptosis after HI in the endothelial-specific IRS-1 transgenic pups. Together, our findings suggested that neuronal and endothelial IRS-1 had opposite effects on the neurovascular integrity and damage after neonatal HI brain injury and that endothelial IRS-1 worsens neurovascular integrity after HI via mTOR-mediated tight junction protein disassembly.

18.
Sci Rep ; 11(1): 3919, 2021 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-33594141

RESUMO

Turbulent mixing in the deep ocean is not well understood. The breaking of internal waves on sloped seafloor topography can generate deep-sea turbulence. However, it is difficult to measure turbulence comprehensively due to its multi-scale processes, in addition to flow-flow and flow-topography interactions. Dense, high-resolution spatiotemporal coverage of observations may help shed light on turbulence evolution. Here, we present turbulence observations from four broadband ocean bottom seismometers (OBSs) and a 200-m vertical thermistor string (T-string) in a footprint of 1 × 1 km to characterize turbulence induced by internal waves at a depth of 3000 m on a Pacific continental slope. Correlating the OBS-calculated time derivative of kinetic energy and the T-string-calculated turbulent kinetic energy dissipation rate, we propose that the OBS-detected signals were induced by near-seafloor turbulence. Strong disturbances were detected during a typhoon period, suggesting large-scale inertial waves breaking with upslope transport speeds of 0.2-0.5 m s-1. Disturbances were mostly excited on the downslope side of the array where the internal waves from the Pacific Ocean broke initially and the turbulence oscillated between < 1 km small-scale ridges. Such small-scale topography caused varying turbulence-induced signals due to localized waves breaking. Arrayed OBSs can provide complementary observations to characterize deep-sea turbulence.

19.
Ecotoxicol Environ Saf ; 210: 111875, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33454577

RESUMO

Coccinella septempunctata (ladybird) is one of the foremost natural predators that feed on aphids. Thus, C. septempunctata serves as an effective biological control agent in integrated pest management (IPM) programs. To supplement the activity of biological control agents, IPM programs often incorporate chemical pesticides to bolster crop protection. To evaluate the effects of a potent insecticide, tolfenpyrad, on C. septempunctata, we tested the sublethal effects of tolfenpyrad on all developmental stages of the life cycle of C. septempunctata and its effects on the next generation. For sublethal testing of the parent generation, the LR50 of tolfenpyrad for C. septempunctata was determined to range from 1.04 to 8.43 g a.i. /hm2 within a set exposure period, while the hazard quotient (HQ) values were above our threshold value of 2 during the entire observation period. These data indicated a potential toxicity risk from tolfenpyrad exposure. The no observed effect application rates (NOERs) of tolfenpyrad on parents (F0) were determined for survival (0.485 g a.i. /hm2), developmental time of pupation (0.242 g a.i. /hm2), and fecundity (0.485 g a.i. /hm2). Application of sublethal doses to unexposed progeny (F1) of exposed parents, prolonged the L1 (1st instar of larvae) and L2 (2nd instar of larvae) stage, while the total longevity, intrinsic rate of increase (r), finite rate of increase (γ), net reproductive rate (R0), and mean generation time (T) were significantly reduced. These results demonstrated the negative influence of sublethal concentrations of tolfenpyrad on C. septempunctata and its persistent effects on subsequent generations.


Assuntos
Besouros/efeitos dos fármacos , Inseticidas/toxicidade , Pirazóis/toxicidade , Animais , Besouros/fisiologia , Feminino , Fertilidade/efeitos dos fármacos , Larva/efeitos dos fármacos , Larva/fisiologia , Estágios do Ciclo de Vida/efeitos dos fármacos , Masculino , Controle de Pragas , Reprodução/efeitos dos fármacos
20.
Healthcare (Basel) ; 10(1)2021 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-35052184

RESUMO

Purpose: With the benefits of advanced medical technology, Taiwan has gradually changed from an aged society to a super-aged society. According to previous studies, the prevalence rate of mild cognitive impairment (MCI) over the age of 60 is 15% to 20%. Therefore, the main purpose of our study was to analyze the correlation of cognitive function with visual function (specifically, binocular vision and visual perception) in Taiwanese volunteers aged 60 years or older. Methods: Thirty-six healthy participants who were not taking psychiatric medications and who had not been diagnosed with any retinal or optic nerve diseases were enrolled. Addenbrooke's cognitive examination III (ACE-III), binocular visual function, and visual perception evaluation were performed, and the data analyzed statistically by t-test, χ2, linear regression, and MANOVA. Results: Cognitive function was closely correlated with visual function and visual perception; the horizontal adjustment time of binocular eye movement, stereopsis, the motor-free visual perception test-4 (MVPT-4), and peripheral awareness actually displayed higher explanatory power in predicting cognitive function. In addition, various interactive parameters between visual function and visual perception were found to affect specific aspects of ACE-III. Discussion: Our study revealed that there was a close correlation of cognitive function with visual function; as such, it may be possible to predict visual function deficits in patients with mild cognitive impairment.

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